James howard



Nu. 6ll,|70. Patented Sept. 20, I898. J. HOWARD.

DRIVING GEAR FOR BIGYGLES.

(Application filed Nov. 16, 1897.)

(No Model.)

UNITED STATES PATENT OFFICE.

JAMES HOWARD, OF LONDON, ENGLAND.

DRIVING-G EAR FOR BICYCLES.

SPECIFICATION forming part of Letters Patent No. 611,170, dated September 20, 1898. Application filed November 16, 1897. $erial No. 658,752. on; model.) Patented in England April 10, 1897, No. 9,167.

To all whom it may concern: I

Be it known that 1, JAMES HOWARD, engineer, a subject of the Queen of Great Britain, residing at 2 Sandfield Terrace, Guildford, London, in the county of Surrey, England, have invented certain new and useful Improvements in Driving-Gears for Cycles or the Like, (for which I have obtained a patent in Great Britain, No. 9,167, dated April 10, 1897,) of which the following is a specification.

The invention relates to means for taking up the slack of drivingchains when used with elliptical chain-wheels, such slackness of the chain occurring when the longer axis of the ellipse is in a horizontal position.

In order that my said invention may be particularly described and ascertained, reference is hereby made to the accompanying drawings, in which similar letters of reference indicate corresponding parts.

- Figure 1 is a front elevation of an elliptical chain-wheel fitted with my improved means for taking up the slack of the chain, Fig. 2 is a sectional plan view of same. Figs. 3 and at are diagrams serving to illustrate the action of the improved apparatus.

According to my invention I provide a triangular oscillatory frame a, suitably mounted loosely on the boss I) of the elliptical chainwheel 0 or on the axle d in such a manner that the chain-wheel c and the axle d are free to revolve in bearings in. the crank-bracket e without causinga similar action on the frame a, which remains in position between forward and backward moving portions of the chain f, Figs. 3 and 4.

The frame a,which can oscillate on the boss I) of the chain-wheel, is provided with a small chain roller or wheel g, suitably mounted on ball-bearings, and is also provided with a short arm h, carrying a small chain-guide wheel g, also mounted on ballbearings. The short arm his pivoted to the frame a at i, the short arm h being controlled in its movement pin Z, fixed in the frame to within the by a coil-spring in the box 7:, which is-arranged to exert its power outward and against the under side of the chain, the construction beingsuch that the arm h, carrying the guidewheel g, can yield on the oscillatory frame a. The motion of the short arm is limited by a formed in the short arm h.

recess m, v

The elliptical wheel may be set at any antaken up, the spring also forcingthe arm hto assumeits relative position at all other. points of the revolution. The frame a also accommodates itself to the action of the small wheels g g.

I claim- I 1. The combination with an axle, and an elliptical wheel, of an oscillatory frame carrying two chain-guide wheels, one of which is yieldingly mounted thereupon, substantially L as described.

2. The combination with an axle, and an elliptical chain-wheel, of an oscillatory frame loosely mounted in operative relation to the chain-wheel and provided with a chain-guide wheel 9 and a pivoted spring-yielding arm h carryinga chain-guide wheel g, substantially as and for the purposes described.

Dated the 24th day of September, 1897.

JAMES HOWARD.

Witnesses:

GEORGE O. DOWNING, WALTER I. SKEETEN. 

